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FAIR VALUE OF FINANCIAL INSTRUMENTS - Assets and Liabilities Measured at Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Dec. 31, 2021
Financial Assets |  |  |
Derivative assets | $ 71,826 |  | $ 45,086
Financial Liabilities |  |  |
Derivative liabilities | 60,586 |  | 40,728
Impaired Loans [Abstract] |  |  |
Individually evaluated CRE loans with an allowance for credit losses, Outstanding balance |  |  | 1,900
With related allowance recorded |  |  | 1,900
(Credit) provision for credit losses | (1,592) | $ 15,779 |
Recurring | Cash flow hedges |  |  |
Financial Assets |  |  |
Derivative assets | 11,240 |  | 4,358
Recurring | Freestanding derivatives, net |  |  |
Financial Assets |  |  |
Derivative assets | 60,586 |  | 40,728
Financial Liabilities |  |  |
Derivative liabilities | 60,586 |  | 40,728
Recurring | Level 2 Inputs [Member] | Cash flow hedges |  |  |
Financial Assets |  |  |
Derivative assets | 11,240 |  | 4,358
Recurring | Level 2 Inputs [Member] | Freestanding derivatives, net |  |  |
Financial Assets |  |  |
Derivative assets | 60,586 |  | 40,728
Financial Liabilities |  |  |
Derivative liabilities | 60,586 |  | 40,728
Nonrecurring [Member] |  |  |
Impaired Loans [Abstract] |  |  |
Individually evaluated CRE loans with an allowance for credit losses, Outstanding balance | 2,500 |  | 2,500
With related allowance recorded | 2,500 |  | 2,500
Valuation allowance | 1,300 |  |
(Credit) provision for credit losses | 757 |  | 600
Nonrecurring [Member] | Level 3 Inputs [Member] |  |  |
Impaired Loans [Abstract] |  |  |
Individually evaluated loans | 1,179 |  | 1,900
Carrying Amount |  |  |
Impaired Loans [Abstract] |  |  |
Individually evaluated loans | 1,200 |  |
Carrying Amount | Nonrecurring [Member] |  |  |
Impaired Loans [Abstract] |  |  |
Individually evaluated loans | 1,179 |  | 1,900
Agency Notes | Recurring |  |  |
Financial Assets |  |  |
Securities available-for-sale: |  |  | 80,254
Agency Notes | Recurring | Level 2 Inputs [Member] |  |  |
Financial Assets |  |  |
Securities available-for-sale: |  |  | 80,254
Treasury Securities | Recurring |  |  |
Financial Assets |  |  |
Securities available-for-sale: | 234,531 |  | 244,769
Treasury Securities | Recurring | Level 2 Inputs [Member] |  |  |
Financial Assets |  |  |
Securities available-for-sale: | 234,531 |  | 244,769
Corporate Securities | Recurring |  |  |
Financial Assets |  |  |
Securities available-for-sale: | 147,425 |  | 152,030
Corporate Securities | Recurring | Level 2 Inputs [Member] |  |  |
Financial Assets |  |  |
Securities available-for-sale: | 147,425 |  | 152,030
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring |  |  |
Financial Assets |  |  |
Mortgage-backed securities | 418,116 |  | 526,454
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs") | Recurring | Level 2 Inputs [Member] |  |  |
Financial Assets |  |  |
Mortgage-backed securities | 418,116 |  | 526,454
Agency collateralized mortgage obligations ("CMOs") | Recurring |  |  |
Financial Assets |  |  |
Securities available-for-sale: | 440,183 |  | 521,258
Agency collateralized mortgage obligations ("CMOs") | Recurring | Level 2 Inputs [Member] |  |  |
Financial Assets |  |  |
Securities available-for-sale: | 440,183 |  | 521,258
State and municipal obligations. | Recurring |  |  |
Financial Assets |  |  |
Securities available-for-sale: | 36,781 |  | 38,946
State and municipal obligations. | Recurring | Level 2 Inputs [Member] |  |  |
Financial Assets |  |  |
Securities available-for-sale: | $ 36,781 |  | $ 38,946

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